(18) BIOMECHANICAL DIFFERENCES BETWEEN TWO- AND THREE-STEP ATTACKING APPROACHES IN FEMALE COLLEGIATE VOLLEYBALL PLAYERS

Despite being a popular team sport worldwide, there is still a lack of scientific literature focused on examining biomechanical characteristics of attacking motions, as one of the fundamental volleyball-specific skills.

Purpose: Thus, the purpose of the present study was to examine the differences in biomechanical characteristics between two- and three-step attacking approaches in female volleyball players.

Methods: Twelve NCAA Division-II athletes (age= 20.4±1.7 yrs; hgt= 178.9±11.7 cm; wgt= 73.4±10.2 kg) participated in the present investigation. Upon the completion of the dynamic warm-up protocol, each athlete performed five two- and three-step attacking approaches while standing on a uni-axial force plate (Roughdeck, Rice Lake Weighing Systems, Rice Lake, WI) with a data acquisition system (BioPac MP 150, Goleta, CA) sampling at 1000 Hz. Each jump trial was separated by 45-60 sec rest interval. The force plate was positioned in volleyball “Zone 4” (i.e., the left side of the net) and an attacking target was positioned at the average female collegiate attacking height of 2.64 m. The following biomechanical variables of interest were analyzed: peak concentric force (PCF) during a penultimate step, PCF during an ultimate step, peak landing force (PLF), and vertical jump height (VJH) based on the flight time. A paired-sample t-test was used to examine statistically significant (p< 0.05) differences in biomechanical characteristics between two- and three-step attacking approaches, and Hedge’s g effect sizes to examine the magnitude of difference between the means.

Results: No statistically significant differences in PLF, VJH, and PCF during both penultimate and ultimate steps were observed between the two- and three-step attacking approaches. Also, the differences in all of the aforementioned variables were trivial in magnitude (g=0.02-0.12).

Conclusions: The findings of the present study reveal that two- and three-step attacking approaches seem to yield similar biomechanical requirements. While further research is warranted on this topic, this may be attributed to hitting target being positioned at the same standardized height, as well as the testing being performed in a controlled laboratory setting. PRACTICAL APPLICATIONS: Overall, these findings may allow practitioners to obtain a deeper insight into the biomechanical requirements of some of the most commonly used attacking approaches that can help with the design of training regimens targeted towards optimizing athletes’ on-court performance.  

Acknowledgements: N/A